Unless you signed a new contract agreeing to the new guideline for fees and notice, you are only obligated to adhere to the old contract in my opinion.
I personally feel that if you paid for a full two weeks up front, and pulled her from care, your two weeks payment is enough to cover the two weeks notice and the provider would owe YOU the return of your deposit.
I also think she has no legal right to go back and charge late fees if she didn't charge them when she should have. If she waived them, that is on her and you shouldn't be "back charged" them now in light of this situation.
VERY unprofessional to do that in my opinion.
As far as the EIN number, she canNOT legal withhold that but what you need to do is submit a W-10 form to her. You can find that here:
http://www.irs.gov/pub/irs-pdf/fw10.pdf
If she refuses to fill out the W-10 form when you submit it to her, she can be fined $50 for refusing to give it out.
You can still do your taxes without it if you know your year end total.
Here is some info about how that works
http://www.tomcopelandblog.com/2011/...47e215dc2e970b
Bottom line is make sure you have a copy of your signed contract with this provider. What is written in the contract is what you are required to do. If you didn't sing the new contract, that one isn't really enforceable.